Method for operating a sensor for detecting at least a portion of a measurement gas component having bound oxygen in a measurement gas

Abstract

A method for operating a sensor for detecting at least a portion of a measured-gas component having bound oxygen in a measured gas in an exhaust gas of an internal combustion engine. The sensor encompasses a sensor element including: a first pump cell; a reference cell; and a second pump cell. An electronic control device is connected to the sensor element; the first pump cell is connected using an electrically conductive connection to a first separate terminal of the device; the second pump cell is connected by an electrically conductive connection to a second separate terminal of the device; a measuring resistor is provided in the connection that connects the second pump cell to the second separate terminal; a current excitation and/or voltage excitation of the second pump cell is carried out using the control device to generate a measured signal at the measuring resistor.

1 - 16 . (canceled) 
     
     
         17 . A method for operating a sensor for detecting at least a portion of a measured-gas component having bound oxygen in a measured gas, in an exhaust gas of an internal combustion engine, the sensor including a sensor element having: (i) a first pump cell that has an external pump electrode and an internal pump electrode and adjoins a first cavity that is in communication with the measured gas, (ii) a reference cell that has a Nernst electrode and a reference electrode and adjoins a reference gas space, and (iii) a second pump cell that has a pump electrode and a counter-electrode and adjoins a second cavity, the sensor further including an electronic control device connected to the sensor element, the electronic control device having at least a first separate terminal for the first pump cell and a second separate terminal for the second pump cell, the first pump cell being connected to the electronic control device using an electrically conductive connection to the first separate terminal, the second pump cell being connected to the electronic control device using an electrically conductive connection to the second separate terminal, a measuring resistor being provided in the electrically conductive connection that connects the second pump cell to the second separate terminal, the method comprising:
 carrying out a current excitation and/or voltage excitation of the second pump cell using the control device to generate a measured signal at the measuring resistor.   
     
     
         18 . The method as recited in  claim 17 , wherein for the carrying out, a predetermined electrical voltage is applied to the second pump cell, the voltage excitation of the second pump cell being carried out, the voltage excitation encompassing a modification of the predetermined electrical voltage for a predetermined time. 
     
     
         19 . The method as recited in  claim 18 , wherein the predetermined electrical voltage is raised for the predetermined time. 
     
     
         20 . The method as recited in  claim 18 , wherein the electrically conductive connection that connects the second pump cell to the second separate terminal is identified as intact when the measured signal has a value not equal to zero for the predetermined time, and is identified as defective when the measured signal has a value of zero for the predetermined time. 
     
     
         21 . The method as recited in  claim 17 , wherein, for the carrying out, a predetermined electrical voltage is applied to the second pump cell, the voltage excitation of the second pump cell being carried out, the predetermined electrical voltage being raised for a first predetermined time, and the predetermined electrical voltage being lowered for a second predetermined time, an integral of the applied electrical voltage having a value of zero for the first predetermined time and the second predetermined time. 
     
     
         22 . The method as recited in  claim 21 , wherein the electrically conductive connection that connects the second pump cell to the second separate terminal is identified as intact when the measured signal has a value not equal to zero for the first predetermined time and the second predetermined time, and is identified as defective when the measured signal has a value of zero for the first predetermined time and the second predetermined time. 
     
     
         23 . The method as recited in  claim 17 , wherein, for the carrying out, a predetermined electrical current is impressed into the second pump cell, the current excitation of the second pump cell being carried out, the predetermined electrical current being raised for a first predetermined time, and the predetermined electrical current being lowered for a second predetermined time, the first predetermined time and the second predetermined time being identical in length. 
     
     
         24 . The method as recited in  claim 23 , wherein the electrically conductive connection that connects the second pump cell to the second separate terminal is identified as intact when an electrical voltage applied to the second pump cell falls below a threshold value for the first predetermined time and for the second predetermined time, and being identified as defective when an electrical voltage applied to the second pump cell exceeds a threshold value for the first predetermined time and for the second predetermined time. 
     
     
         25 . The method as recited in  claim 17 , wherein, for the carrying out, a predetermined electrical voltage is applied to the second pump cell, and the voltage excitation of the second pump cell is carried out, the voltage excitation encompassing a periodic modification of the predetermined electrical voltage. 
     
     
         26 . The method as recited in  claim 25 , wherein a period length is less than an electrochemical time constant of the second pump cell. 
     
     
         27 . The method as recited in  claim 25 , wherein the measured signal is filtered using a low-pass filter, the predetermined electrical voltage being modified at a frequency that is greater than a bandwidth of the low-pass filter. 
     
     
         28 . The method as recited in  claim 25 , wherein the electrically conductive connection that connects the second pump cell to the second separate terminal is identified as intact when the measured signal exhibits a periodic change, and being identified as defective when the measured signal exhibits no periodic change. 
     
     
         29 . A non-transitory electronic storage medium on which is stored a computer program for operating a sensor for detecting at least a portion of a measured-gas component having bound oxygen in a measured gas, in an exhaust gas of an internal combustion engine, the sensor including a sensor element having: (i) a first pump cell that has an external pump electrode and an internal pump electrode and adjoins a first cavity that is in communication with the measured gas, (ii) a reference cell that has a Nernst electrode and a reference electrode and adjoins a reference gas space, and (iii) a second pump cell that has a pump electrode and a counter-electrode and adjoins a second cavity, the sensor further including an electronic control device connected to the sensor element, the electronic control device having at least a first separate terminal for the first pump cell and a second separate terminal for the second pump cell, the first pump cell being connected to the electronic control device using an electrically conductive connection to the first separate terminal, the second pump cell being connected to the electronic control device using an electrically conductive connection to the second separate terminal, a measuring resistor being provided in the electrically conductive connection that connects the second pump cell to the second separate terminal, the computer program, when executed by a computer, causing the computer to perform:
 carrying out a current excitation and/or voltage excitation of the second pump cell using the control device to generate a measured signal at the measuring resistor. 
 
     
     
         30 . An electronic control device configured to operate a sensor for detecting at least a portion of a measured-gas component having bound oxygen in a measured gas, in an exhaust gas of an internal combustion engine, the sensor including a sensor element having: (i) a first pump cell that has an external pump electrode and an internal pump electrode and adjoins a first cavity that is in communication with the measured gas, (ii) a reference cell that has a Nernst electrode and a reference electrode and adjoins a reference gas space, and (iii) a second pump cell that has a pump electrode and a counter-electrode and adjoins a second cavity, the electronic control device comprising:
 at least a first separate terminal for the first pump cell and a second separate terminal for the second pump cell, the first pump cell being connected to the electronic control device using an electrically conductive connection to the first separate terminal, the second pump cell being connected to the electronic control device using an electrically conductive connection to the second separate terminal, a measuring resistor being provided in the electrically conductive connection that connects the second pump cell to the second separate terminal;   wherein the electronic control device is configured to carry out a current excitation and/or voltage excitation of the second pump cell to generate a measured signal at the measuring resistor.   
     
     
         31 . A sensor for detecting at least a portion of a measured-gas component having bound oxygen in a measured gas, in an exhaust gas of an internal combustion engine, comprising:
 a sensor element including a first pump cell that has an external pump electrode and an internal pump electrode and adjoins a first cavity that is communication with the measured gas, a reference cell that has a Nernst electrode and a reference electrode and adjoins a reference gas space, and a second pump cell that has a pump electrode and a counter-electrode and adjoins a second cavity; and   an electronic control device connected to the sensor element, the electronic device having at least a first separate terminal for the first pump cell and a second separate terminal for the second pump cell, the first pump cell being connected to the electronic control device using an electrically conductive connection to the first separate terminal, the second pump cell being connected to the electronic control device using an electrically conductive connection to the second separate terminal, a measuring resistor being provided in the electrically conductive connection that connects the second pump cell to the second separate terminal, electronic control device configured to carry out a current excitation and/or voltage excitation of the second pump cell to generate a measured signal at the measuring resistor.